Prediluted lubricating oil



wax-bearing lubricating oil, for example a' Pressed paraflin base oil (viscosity 300 sec.

Patented Nov. 10, 1931 UNITED STATES' PATENT OFFICE ROBERT E. WIDSON, 01 CHICAGO, ILLINOIS, ASSIGNOR '10' STANDARD OIL COMPANY, OI

WRITING, INDIANA, A CORPORATION OF INDIANA IPBIEDILUTED LUBRICATING OIL No Drawing.

.This invention relates to prediluted lubricating oils which are intended to be In a condition of substantial equilibrium with respect to dilution under average operatmg conditions of automobile or other motors, and which do not, therefore, materially change in viscosity during normal use. The mvent on relates particularly to such oils comprlsing low pour test lubricants derived from waxbearing crude.

In accordance with the present invention residual oil derived from the reductionof once pressed wax distillate, is diluted w1th heavy naphtha which is suitable for use as an equilibrium diluent. The diluted 011 1s chilled and pressed, settled or centrifuged to remove wax. The dewaxed oil is embodied in a prediluted lubricating oil, the heavy naphtha constituting the diluent or a part of the diluent, thereof. If, in any case, it is necessary to employ, for wax removal,'a larger amount of naphtha than is appropriate 1n the finished lubricant, the excess may be readily removed by evaporation at any time after dewaxing. In such a case, it is preferred to employ a slightly lighter naphtha and to remove the lighter portion after dewaxing, so that naphtha of the appropriate composition and in proper amount remains in the oil.

The invention will readily be understood from the following description of a specific example.

A satisfactor prediluted medium motor oil may be constltuted as follows:

Per cent Saybolt at 100 F.) 36 Filtered cylinder stock 18 Low cold test naphthenic base oil 36 Heavy naphtha (300 to 460 F. boiling range) 10 The pressed parafiin base oil is prepared as follows. Wax distillate, also known as paraffin distillate, is pressed once in the usual way for removal of wax. Thereafter the distillate is reduced for the production of light lubricating oils and a red oil of about 300 sec. Saybolt viscosit at 100 F. The average yield of such a eavy red oil is about 15%.

Application filed July 2, 1928. Serial No. 290,051.

To 36 parts of this red oil 10 parts of heavy naphtha of the boiling point range 300 to 460 F. are added, giving a mixture with a viscosity of about sec. at F. This mixture is chilled in the usual manner to about 10 F. and the wax is removed by pressing or centrifuging. The lowcold test oil thus obtained may be blended directly with the cylinder stock and naphthenic base oil to give a diluted lubricating oil of the composition set forth above.

Although the present invention has been described in connection with details of aspecific example, it must be understood that such details are not intended to be limitative upon the scope of the invention except in so far as included in theaccompany-ing claims.

I claim:

1. The method of producing a prediluted lubricating oil which consists in adding heavy naphtha to a wax-bearing lubricating oil, chilling the diluted oil, removing wax therefrom and embodying the dewaxed oil and heavy naphtha in a prediluted lubricating oil.

2. The method of producing a prediluted lubricating oil which consists in adding heavy naphtha to wax-bearing lubricating oil 1n suflicient quantity to facilitate wax removal at low temperatures, chilling the mixture, removing wax therefrom and mixing the oil with other lubricant oils.

3. The method of producing a. prediluted lubricating oil which consists in pressing parafin distillate, reducing said distillate thereby producing a heavy lubricating oil, diluting said heavy oil with heavy naphtha, chill-. mg the mixture and removing wax therefrom, and blending the mixture with other lubricant oils. I a

4. The method of producing a prediluted lubricating oil which consists in pressing paraifin distillate, reducing saiddistillate thereaflin distillate, reducing said distillate thereby producin a heavy red oil diluting said 7 .heavy red 01% with heavyv naphtha, chilling the mixture and removing wax therefrom, and blending the mixture with low cold test na hthenic base lubricating oil and filtered cy der stock.

6. The method of motor lubricating oil whlch conslsts m pressing a wax distillate, reducing said distillate to a 15% bottom having a viscosity of about '300 sec. Saybolt at 100 F, adding heavy naphtha having a boiling range between about 300 and 460 F., to said resldual oil in the roportion of about 10 parts of naphtha to a out 36 parts of the red oil, thereby giving a mixture with a viscosity of about sec. Saybolt at F., chilling the mixture to about -10 F removing wax and blending the dewaxed mixture with about 18 parts a of filtered cylinder stock and about 36 parts of low cold test naphthenic base lubricating oil.

In testimony whereof I have hereunto set my hand this 31st da of May 1928.

- no ERT 1t. WILSON.

preparing a prediluted. 

